Physical and chemical oceanographic data during Umitaka-maru cruise of the 59th Japanese Antarctic Research Expedition in January 2018

Connecting all major ocean basins, the Southern Ocean is pivotal in the meridional overturning circulation of the global oceans. High quality physical and chemical oceanographic data in the Southern Ocean are thus critical for improved understanding of future climates. As a part of the 59th Japanese Antarctic Research Expedition research project, we have obtained high quality Conductivity Temperature Depth (CTD) and water sampling data (salinity, dissolved oxygen, and nutrients) at 6 sites located along 110 degree E transect, the southern end of which reached the sea ice edge. Sea surface temperature and salinity were continuously obtained with a Thermosalinograph (TSG) along cruise track taken between Ports of Fremantle and Hobart, except for Australian Exclusive Economic Zone. Data quality was validated by following as far as possible the recommendation for instruments and methods of Global Ocean Ship-Based Hydrographic Investigation Program. CTD and water sampling data are provided in Exchange formats for World Ocean Circulation Experiment Hydrographic Program CTD and bottle data; TSG data are in simple .csv format.南大洋（Southern Ocean）连接全球所有主要海盆，在全球海洋经向翻转环流中发挥关键作用。因此，获取高质量的南大洋物理与海洋化学数据，对深化未来气候认知至关重要。本数据集作为第59次日本南极考察项目的一部分，科研团队在沿东经110°断面的6个站位采集了高质量温盐深仪（Conductivity Temperature Depth, CTD）及采水瓶水样数据，检测指标涵盖盐度、溶解氧与营养盐，该断面南端延伸至海冰边缘。科研航次在弗里曼特尔港与霍巴特港之间的航行轨迹上，通过海水温盐仪（Thermosalinograph, TSG）连续采集海表温度与盐度数据，但未覆盖澳大利亚专属经济区（Australian Exclusive Economic Zone）海域。本数据集严格遵循全球海洋船舶水文调查计划（Global Ocean Ship-Based Hydrographic Investigation Program）的仪器操作与数据处理规范开展质量验证。温盐深仪及采水瓶水样数据以世界海洋环流实验水文计划（World Ocean Circulation Experiment Hydrographic Program）指定的交换格式存储；海水温盐仪数据则采用通用.csv格式提供。